When a person (“subject”) follows an exercise program in a gym or comparable environment, progress of the subject and compliance with the program is typically monitored manually by the subject or not monitored at all. This has a number of undesirable consequences. For instance, recording of exercises is prone to errors, inaccuracies and omissions. It is also labor-intensive and typically inconsistent among different exercise apparatuses and gyms. US patent application publication 2010/216600 by Kent Noffsinger et al. discloses a strength training apparatus with automatic exercise monitoring. The Noffsinger apparatus suffers from a number of residual problems, however. For instance, since the resistance against which the subject is exercising is generated in an unconventional manner, the Noffsinger apparatus has poor compatibility with other strength training apparatuses, which is why its use may not be usable as evidence for compliance with planned therapies. To a lesser degree, variations among apparatuses of any type make it difficult to monitor the subject's progress with precision. Another problem is that automatic progress monitoring systems do not detect or adapt to situations wherein the subject is more than usually prone to injury. A yet further problem is that automatic progress monitoring systems from different providers are incompatible with each other.